Suspicious WMI Image Load from MS Officeedit

Identifies a suspicious image load (wmiutils.dll) from Microsoft Office processes. This behavior may indicate adversarial activity where child processes are spawned via Windows Management Instrumentation (WMI). This technique can be used to execute code and evade traditional parent/child processes spawned from Microsoft Office products.

Rule type: eql

Rule indices:

  • winlogbeat-*
  • logs-endpoint.events.*
  • logs-windows.*

Severity: low

Risk score: 21

Runs every: 5 minutes

Searches indices from: now-9m (Date Math format, see also Additional look-back time)

Maximum alerts per execution: 100

References:

Tags:

  • Elastic
  • Host
  • Windows
  • Threat Detection
  • Execution

Version: 7 (version history)

Added (Elastic Stack release): 7.11.0

Last modified (Elastic Stack release): 8.4.0

Rule authors: Elastic

Rule license: Elastic License v2

Investigation guideedit


Rule queryedit

any where (event.category == "library" or (event.category ==
"process" and event.action : "Image loaded*")) and process.name :
("WINWORD.EXE", "EXCEL.EXE", "POWERPNT.EXE", "MSPUB.EXE",
"MSACCESS.EXE") and (dll.name : "wmiutils.dll" or file.name :
"wmiutils.dll")

Threat mappingedit

Framework: MITRE ATT&CKTM

Rule version historyedit

Version 7 (8.4.0 release)
  • Updated query, changed from:

    library where process.name : ("WINWORD.EXE", "EXCEL.EXE",
    "POWERPNT.EXE", "MSPUB.EXE", "MSACCESS.EXE") and event.action :
    "load" and event.category : "library" and dll.name :
    "wmiutils.dll"
Version 5 (8.2.0 release)
  • Formatting only
Version 4 (7.15.0 release)
  • Formatting only
Version 3 (7.12.0 release)
  • Updated query, changed from:

    library where process.name in ("WINWORD.EXE", "EXCEL.EXE",
    "POWERPNT.EXE", "MSPUB.EXE", "MSACCESS.EXE") and event.action ==
    "load" and event.category == "library" and file.name ==
    "wmiutils.dll"
Version 2 (7.11.2 release)
  • Formatting only